Experts to give verdict on direct action

Key climate change experts are set to deliver their verdicts on the Abbott government's proposed alternative to the carbon tax - its direct action plan.

Heavyweights from the CSIRO, Clean Energy Finance Corporation and the Climate Change Authority will front a Senate committee hearing in Canberra on Friday.

Ross Garnaut, who conducted two reviews into global warming for the previous Labor government, will also give evidence.

Climate Change Authority chair Bernie Fraser says major political parties need to show more than lip service to climate change science.

"It has to be backed by policy measures commensurate with the challenges identified by climate scientists," he said in a submission to the inquiry.

Meanwhile, Prime Minister Tony Abbott will deliver an address to the United Nations International Women's Day breakfast in Sydney on Friday.